So you've got these gorgeous knives. Now what do you do with them?

Professional chefs treat their knives like precious cargo, carrying them around in briefcases wherever they go. The chef's knives are usually exclusively the chef's knives -- no one else would dream of touching them.

Once you've collected a particular combination of knives that serves your particular purposes, the next trick is to keep them sharp and make them last. A dull knife is worse than inefficient and frustrating for the cook. It's also bad for the food -- it tears and mashes instead of actually cutting.

Any knife, even with the best care, will get dull. But it will get dull a lot faster if it's neglected, and it will get irreversibly dull if it's neglected for long.

All knives, whether they're carbon steel or stainless, should be stored where their edges don't get banged around. If a knife rattles around in the utensils drawer it's apt to get dulled or even nicked, especially if its blade is carbon steel. Three common ways of storing are the magnetic knife rack, the wooden knife holder that sits on a counter, or, if you have the drawer space, a magnetic rack installed crosswise at the bottom of a shallow drawer on which you lay out your knives so that they are easily visible but won't rattle around with each other.

Stainless knives, whether they have a high percentage of carbon steel or not, are no problem to keep clean. Although some manufacturers claim these knives are dishwasher proof, there are reasons not to wash them in the dishwasher. For one thing, they are apt to rattle around during the cycle, making them a danger not only to their own edge but also to glassware and other breakables. For another, the harsh detergents and high heat are hard on wood handles and can even affect the temper of the steel. Soaking should be avoided too, mostly for the handle's sake.

Stained carbon steel knives (the ones that rust) can be cleaned with a steel scouring pad or with an abrasive cleanser like Ajax. They will always darken with use, however.

Keeping knives sharp is in some ways the most important aspect of their care. If you watch an expert using a knife, chances are great that you'll also see him sharpen it. Francois Dionot of the Bethesda cooking school L'Academie de Cuisine teaches his students to sharpen their knives once for every five minutes of use. During the course of boning a chicken, for instance, the knife might be sharpened several times. Carbon steel knives (the ones that rust) lose their edge the fastest, but they are also much easier to resharpen than their stainless cousins. Pure stainless blades, as opposed to those called "high-carbon stainless," are impossible to sharpen at home once they have lost their edge, and must be professionally reground or in some cases abandoned.

Professionals invariably use a sharpening "steel" for everyday sharpening. The steel is a long piece of solid metal with narrow grooves manufactured lengthwise into it. It has a wooden handle, and most often a guard between handle and metal. The knife blade is held against the steel at a 20-degree angle, handle end of blade against handle end of steel. The blade is drawn down the length of the steel in such a way that the tip of the blade is reached at the same time as the tip of the steel. (If you're sharpening a very short knife on a regulation-sized steel, it obviously won't come out quite even.)

Some cooks like the shorter ceramic sharpeners, says Melissa Mayor of Kitchen Bazaar, because they are easier to handle. Mayor advises that when sharpening with a steel, the knife blade moves, but when sharpening with a ceramic such as "Zip-Zap" the sharpener moves. The 20-degree angle is maintained in either case.

The advantage the steel has is its length, which, according to Leslie Hagan of La Cuisine, should be as long as the blade of your longest knife.

In some stores you will run across steels of varying degrees of coarseness. The very coarse are for sharpening very dull blades, the very fine ones are for finishing blades that have been reground or honed. For average home use a steel of medium coarseness is best. Steels range in price from under $10 to close to $50, but for $10-$20 you should be able to get a long steel of medium coarseness that will last a very long time.

Once a knife cannot be satisfactorily sharpened with a steel or ceramic, it needs professional work. Most hardware stores sharpen knives, and at least two kitchenware stores do, too. Kitchen Bazaar stores will sharpen any carbon or high-carbon, no-stain knife for a minimum 20 cents per inch. Its equipment cannot sharpen pure stainless steel, and its staff can't do much to repair nicks or gouges.

La Cuisine in Alexandria sharpens carbon steel knives for $1 a blade, stainless for $2. If the knife is damaged (nicked blade, broken tip) the store can usually repair it but the charge will be from $4 to $10 depending on the knife and the extent of damage.